Just firing up my newly rebuilt TBI and notice that immediately upon firing the engine the factory oil pressure gauge pegs out. My gauge goes to 60psi...the needle goes all the way to the needle stop. So I don't know how high the pressure is actually going.

I'm using Royal Purple engine break-in oil.

Is this something I should be worrying about? What could be causing it?

I guess the first thing to check will be the sending unit, but sure it is not shot.....but after that?

 

High oil pressure is caused by tight tolerances between bearing surfaces. The pressure will most likely reduce somewhat after break-in. Which type of oil pump was installed? Stock, high pressure, high volume?

The sender or the gauge could also be acting up. GM isn't exactly known for accuracy of gauges on older vehicles.

 

Thanks for the feedback snardos,

I assume it is a stock oil pump, this was not a hi-po rebuild.

I'm just really worried, this is my first "new" engine fire up and break in, and I keep reading all this stuff about cam break in and how important it is to fire up on the first turn of the key and rev up for cam break in. Of course that hasn't worked for me, I've had to crank the einge 20 times before I found other issues before the engine actually fired.

Also priming the oil system, I did take apart a distributor and prime a little with the drill, but now I'm pretty sure I didn't do it well enough (didn't rotate the engine while priming) also there were many many days (read 'weeks') between priming the engine and first crank of the egine.

So now I'm really nervous about every little thing, every sounds, squeal, banks, clunk, at this point I've almost convinced myself the engine is junk and I've ruined it already.

now seeing the oil pressure shoot so high, I'm could of just jumped off a cliff, I was sure it meant I did something bad.

It is pretty scary when you've put so much time and money into a project, then it comes down to the moment when you fire the engine, and you might be ruining it all!

I really appreciate people feedback and help who've done this stuff before.

 

My OP gauge is extreamely irratic at best. What do I need to do? ~stocker L03~

 

You can try replacing your oil pressure unit. It's a $20.00 part that takes about 10 minutes to replace.

 

I figured it would be that or my cluster. Where is it located?

 

I have no idea on a 91, but for my 84 it's just on the driverside near the distributor, behind the intake manifold.

 

Thanks, Ill check in tomorrows daylight.

 

On a 91 the oil pressure sending unit is near the filter.

 

I take it that its obvious when I get under there to look?

 

Yea pretty much, its a small tube that has a connector going to it. Somewhere close to the filter. Its not very easy to get at unless you have a really deep socket but its pretty hard to miss if your looking for it.

 

Thanks for the help, let it be known that its appreciated. Luckily I already have a socket designed for oil pressure sensors A tube, shouldnt it have wires? Thought it was all electrical, no?

 

worse comes to worse just turn the old one out with vice grips. They aren't tightened very much. You should be able to get a wrench on it though (along with the new one as well). High volume oil pumps are cheap as hell. Even if it was a stock rebuild i wouldn't be surprised if whoever did it used a melling hi volume one. They are readily available at most part stores and usually stocked so...

and yes it will have a 2 wire connection going to it.

 

Back to the Original Post:

Big6ft6 - What year is the motor? If it is an 87 or newer roller block, cam break-in is not as big of a deal as with flat tappet cams. I wouldn't be too worried about the breakin anyway because by now if there was damage, there wouldn't be anything you could do about it. I have read a lot of different break-in procedures but the general understanding is that it isn't as big a deal as it used to be.

You should probably get a mechanical oil pressure guage to make sure of the pressure, and listen closely for any abnormal noises. You could also pull off a valve cover and make sure oil is getting to the top of the motor. The only thing that would worry me about high oil pressure would be that there was a blockage somewhere causing the oil to not flow.